Lubricating compositions



Patented Nov. 11,1952

LUBRICATING COMPOSITIONS Wilfred Pohl, Harrow, England, assignor to Shell Development Company, San Francisco, Calif., a corporation of Delaware N Drawing.

This invention is concerned with lubricating compositions and in particular with lubricating compositions suitable for the lubrication of marine engine bearings.

The lubrication of the bearings of marine engines presents a special problem in that condensed steam, often in considerable quantity, finds its way from the cylinders on to the bearings or at least on to those located below cylinders or piston rods. Accordingly the bearing lubricant employed should function successfully in the presence of water and to this end it should have the property of forming stable water-in-oil emulsions when agitated with water. Furthermore such water-in-oil emulsions, on further addition of water, should not invert to an oil-inwater emulsion. Whereas water-in-oil emulsions tend to adhere to the metallic surfaces to be lubricated and thus maintain a film of lubricant on the surfaces, oil-in-water emulsions tend to drain 01f the metal surfaces and to be readily washed off by freshly condensed steam and thus result in poor lubrication. Lubricants exhibiting the property of forming stable water-in-oil emulsions which do not invert to oil-in-water emulsions on dilution with water, are hereinafter referred to throughout as marine engine lubricants.

- ,Marine engine lubricants available in oommerce include compositions consisting of a blend of a suitable mineral lubricating oil with an air blown semi-drying fatty oil such as rapeseed oil or fish oil. These air blown semi-drying oils, when used in sufiicient quantities, usually -20 per cent by weight of the composition, promote the formation of substantially stable water-inoil emulsions.

The availability of these air blown semi-drying oils however, is frequently restricted to an extent which compels the use of substitute materials. Reduction of the quantity of air blown fatty oil employed ultimately results in lubricating compositions possessing inadequate emulsification and therefore defective lubricating properties. It is an object of the present invention to provide means whereby substantial reduction in the amounts, of blown fatty oil incorporated in marine engine lubricants can be effected without adverse effect on their lubricati p e sr s- .1 i

Application January 24, 1949, Serial No. 72,557. In Great Britain February 10,

11 Claims. (01, 2'52 ss.4)

It has now been discovered that the quantities of these blown fatty oils blended into marine engine lubricants can be substantially reduced and the lubricant nevertheless markedly improved by addition of basic salts of oil-soluble sulfonic acids broadly represented by the general formula R wherein B may be a petroleum hydrocarbon radical, an aliphatic hydrocarbon radical or a monoor polynuclear aromatic hydrocarbon radical; R

may be one or more alkyl, alkoxy, aroxy, alkyl mercap-to, arylmercapto, alkyl seleno, aryl seleno,

alkyl telluro, aryl telluro radicals; Y may be oneor more polar radicals such as OH, SH, SeH, Tel-I, NR2, CN, and the like; X is the sulfo radical; the sum of n and a: is the valence of the polyvalent metal M, preferably being a divalent metal of the alkaline earth group such as calcium, barium, strontium and magnesium, or the other polyvalent metals such as lead, zinc, tin and aluminum.

Accordingly, the present invention provides marine engine lubricants containing one or more blown fatty oils, and one or more basic sulfonates as broadly defined by the above formula, in amounts suflicient to stabilize and improve the compounded lubricant. The blown fatty oils employed in accordance with this invention are derived from fatty oils of the semi-drying type by blowing air or other oxygen-rich gas through them at an elevated temperature.

Specifically the fatty oils which are particularly suitable for use in compositions of this invention are: corn oil, cottonseed oil, kapoc oil, rapeseed oil, Ravison oil, sesame oil, sunflower oil, teaseed oil, rice bran oil, maize-oil, as well as semi-drying fish and marine oils, such as whale oil and the like, or mixtures of such oils. These oils may be oxidized by such means as are disclosed in the following U. s. Patents 1,863,004, 2,043,923, 2,156,226, 2,186,910, and 2,216,222. If desired, mixtures of oxidized fatty oils with minor proportions not more than 0.1% in weight, of non-oxidized fatty oils can be used as well as derstood however, that blown drying-oils such as linseed oil or blown non-drying oils, such as talloW are not included within the scope of the blown fatty oils used in compositions of the present invention. However, minute amounts of non-drying oils such as tallow, lard oil, castor oil, palm oil, and the like, can be admixed with compositions of this invention, if desirable.

The basic metal salts employed in lubricating compositions of this invention are the basic salts of oil-soluble :sulfonic acids. Sulfonic .acids which are particularly desirable :.-.are .obtained as by-products arising during the refining of mineral lubricating oil distillates for the production of white oils, transformer oils or medicinal .oils or other highly refined oils, by treatment with sulfuric acid, oleum or sulfuryl-chloride. Such treatment actually gives risetoftwo distinct types of naphtha-sulfonic acids, one of which, the socalled sludge or green acids, is found in the acid sludge and is water-soluble. The present invention is not concerned with salts of acids of this type. The other type of naphtha-sulfonic acids remains in the oil, and, after separation of the acid sludge, can be extracted from the oil by means of alcohol or alcoholic alkali. .Sulfonic acid :byproducts .of .this ;latter type, generally known and herein ireferred to :as oil-soluble naphthasulfonic acids, ,yield basic alkaline earth -metal salts useful in the lubricating .compositions -of this :invention. .These basic .salts are made by conventional methods of neutralization or double decomposition, an excess of the alkaline earth metal compound over that required to form a neutral salt being employed. However, insuch conventional processes of ,preparation, it .is,possible that a certain amount of neutral .saltQis formed .and .the employment of mixtures of basicand neutralsaltsis within the scope of thisinvention. Conveniently, the basic alkaline earth metal salt may be formed in situ in the mineral oil to be used as a base for the finished lubricating composition. Thus a suitable mineral :lubricating oil maybe treated with asulfonating agent such. as sulfuric 1 acid or oleum in -the .normal way, the oil containing oil-soluble naphtha-sulfonic acids separated from the acid phase and then reacted with an alkaline earth hydroxide such as calcium hydroxide, dry or as an aqueous slurry, in about 100 percent excess of the .quantity irequired to .form the neutral sulfonate. This-process, after removal :of water if ,present, yields an oilconcentrate of the additive which may be blended with further .quantities-of mineral lubricating ioil and withza blown fatty oil to give :a :lubricating composition .falling within the :scope 'of this invention.

Alternatively, the basic alkaline earth :salts may be prepared from-the sodium salt of an oilsoluble naphtha-sulfonic acid or 'from'a'ffreeoilsoluble naphtha-sulfonic acid by treatmentwith, for example, the hydroxide of an alkaline earth metal in excess of that necessary to .form :the neutral salt.

.Other oil-soluble organic sulfonic acids may also be produced by sulfonating alkyl aromatic hydrocarbons, such as alkyl benzenes, alkyl naphtha'lenes,alkylanthracenes, alkyl phenanthrenes, alkyLpicenes, alkyl crisenes, alkyl 'diphenyls, etc. provided the number :of carbon atoms in the alkyl chain or chains is suflicient to render the resulting sul'fonic acids and their salts soluble in the 'base. It is desirable that at .least one alkyl radical vbe relatively long, ri.-e., contain at least 3 .or more carbon atoms, not only because of solubility in oils, but also for the reason that long alkyl chains improve the anti-ring-sticking emciency of the salts formed with the sulfonic acids thereof. Thus, one may produce an aromatic hydrocarbon suitable for the production of highly efficient sulfonic acids by condensing chlorinated paraffin wax, alkyl chlorides such as octyl, decyl, cetyl, and dodecyl chlorides, fatty alcohols, long-chain olefins such as may be obtained in the cracking of wax, with aromatic hydrocarbons by means-tof suitable condensing agents such as -Eriedel- Crafts catalysts, sulfuric acid, phosphorus pentasulfide, phosphoric acid, ietc. Sulfonic acids may contain substituent radicals as, for example, paraffin Wax substituted naphthalene monosulfonic acids which contain a :sulfonic radical attached to one ring of the :naphthalene nucleus and a hydroxy or amino :radi'cal attached to the other ring. Any of these sulfonic acids may be converted to the basic salt .in the manner described above.

Among the basic salts and mixtures thereof which are particularly preferred are:

Basic calcium salt of oil-soluble petroleum sulfonic acid Basic barium salt -of cil-sz'aluble "petroleum sulfonic acid Basic strontiumsalt of oilsolublepetroleum'sulfonic acid Basic magnesium "salt of oil-soluble petroleum "sulfonic acid Basicaluminum salt of oil-soluble petroleum sulfonicacid Basic calcium *sa'ltof 'alkyl naphthalene sulfoiiic iaci'd Basic calcium salt 'o'fdiwax.'benz'enesulfonic acid Basic barium salt of "diwaxbjenzene sulfonic acid Basic calcium salt of alkyl ,phenol sulfonic acid Basic calcium salt .of diwax 'thiophenol sul'fonic 'acid Basic"magnesium salt of diwax thiophenol sulfonic acid Basic lead salt of oil-soluble petroleum .sulfonic acid Basic calcium .salt of 'diwax naphthalene disulfonic acid Basic calcium salt of diwax benzene .disulfonic .Jacid Basic magnesium salt of diwax benzene .disulfonic acid Basic calcium salt of .sulfonated castor oil The mineral lubricating oils which form the major proportion of .my :marine engine lubricants may be .of any type. .Thus they may be derived from parafiinicor asphaltic residues of petroleum :oilsand they may be refined by any of the :many .known solvent extraction and/or solvent dewaxing processes or by the conventional methods of acid refining. Blends of different mineral lubricating oils may of course also be employed. A preferred oil is'an-acid 'refined oil with a viscosity 'of about "250, seconds Redwood at The "natural hydrocarbon oils may be blended with other .oleaginous .materials of lubricating viscosity, including synthetic lubricants, such as "polymerized olefins, copolymers of alkyleneglycols and alkylene oxides,-organic esters,-e. g. 'Z-ethyl hexyl sebacate, dioctyl phthalate, trioctyl phosphate, polymeric tetrahydrofuran, polyalkyl silicone polymers, e. g. 'dime'thyl silicone polymer, or the "synthetic lubricants may be used 'in place of the natural hydrocarbon oil.

In addition to the two additives or this inven- :acimea 55 tion which are admixed with a base oil to form the desired marine engine lubricant, this lubricant may also contain small amounts of other additives such as fatty oils or fats provided that such oils or fats are not of such a nature and are not used in such quantities as to effect adversely the emulsification characteristics of the lubricating compositions. Among such agents may be included acidless tallow, lard oil, oiliness agents, e. g. methyl stearate, extreme pressure agents containing halogen, sulfur and/or phosphorus. oxidation inhibitors such as alkylated phenols and the like.

General formulation of compositions of this Example IV Further illustrative specific combinations of this. invention are shown in Table II, each cominvention may be represented as shown in 15 ponent of which may be used in amounts within Table I. the ranges as indicated in Table I.

TABLE II Components 1; 2, 3- .4 a -1. 9 1 1 Blown rapeseed oil Blown cottonseed oiL.

Blown maize oil Blown whale oil Basic calcium salt of sulfon1cacid.. x x x x Basic masnes umsalt leumsulionic acid x x Basic barium 'salt of oil-soluble petroleum sulionic acid ionic acid Basic barium salt of diwax benzene sulfonlc ac Basic barium salt 01 alkyl naphthalene sul- Voltolized rapesecd oil v ionic acid Acidless tallow' TABLE Broad Limited Range Range Percent Percent Blown fatty oil (semi-drying) 1-5 2. 5-5 Basic metal salts of oil-soluble sulfonic ac1ds 0. 01-5 0. 1-0. 5 Other agents, e. g. oiliness agents, extreme pressure agents, etc 0.1-5 0. 5-1. 5 Base (petroleum hydrocarbon oil and/or synthetic oil) Balance Balance The following examples are given by way of illustrating the lubricating compositions within the scope of this, invention, all parts being parts by weight: I

Example I 96.75 parts acid refined lubricating oil of viscosity 250' Red. at 140 F. 3 parts blown rapeseed oil 025 parts basic calcium salt of oil-soluble naphtha-sulfonic acids Ercamplev II 96.75 parts acid refined lubricating. oil of viscosity 2 Red. at 140 F.

3 parts blown fish oil 0.25 parts basic calcium salt of oil-soluble naphtha-sulfonic acids Example III The above compositions, can be incorporated with a mineral oil or they can be admixed with synthetic oils or a synthetic oil can be used as a base.

With a view to determining the properties and value of the lubricating compositions of this invention, certain laboratory test methods were employed of which the following two are here mentioned, namely the United States Bureau of Ships Emulsion Test (Federal Catalogue320; l4) and an Inversion Point Test. This latter test is a modification of the United States Bureau of Ships Emulsion Test adapted to determine the point at which a water-in-oil emulsion inverts to an oil-in-water emulsion. The apparatus is. that employed. in the United States Bureau of Ships Emulsion Test and the procedure is as follows: 20 ml. of the oil are placed in the cylinder. The stirrer is started and. 0.5 ml. portions of water are added every half minute. After 5 ml. of water have been added, the emulsion is stirred for a further minute and a sample is then examined to ascertain the type of emulsion. After the emulsion has stood for 5 minutes, the stirrer is again started. and the above process is repeated for every 5 m1. of water added. An oil suitable for use as a lubricant for marine engine bearings should give a Water-in-oil emulsion which does not invert to an oil-in-water emulsion onthe addition of 35 ml. of water by the method of this test.

Table III contains the results obtained when the marine engine lubricants described in the foregoing examples and when some closely related, compositions outside. the scope: of this invention, are subjected: to the above. two. tests.

'TABLEIII I I U. S. Bureau of Ships Test No. Lubricating COIHPQSltlOHV V Emulsion Test Inversion Point Test 1 As in Example I Stable water-in-oil Water-in-oil emulsion emulsion. persists in presence of l 35 cc. water. As in Example II do 7 Do. As in'Example III do Do. As in Example I, omitting the Unstable emulslon. basic calcium salt. As in Example I, replacing the do basic salt by the corresponding j neutral salt.

The lubricating oil of Example I Stable water-in-oil Water-in-oil emulsion containing per cent by weight emulsion. persists in presence of of blown rapeseed oil. 35 cc. water.

As in Example II, omitting the Unstable emulsion.

basic calcium salt.

Referring to Table III, a comparison of tests 1, 4. A marine engine lubricant capable of form- 4 and 6 demonstrates that, although lubricating ing a stable emulsion when in contact with an compositions having the desired properties are aqueous medium, containing from 2% to 5% of obtainable by the simple blendin of blown fatty blown rapeseed oil and from 0.1% to 5% of basic oil with a mineral lubricating oil if the blown barium salt of oil-soluble petroleum sulfonic acid fatty oil is present in sufficiently large quantities, and the balance being a mineral oil.

the use of small quantities of blown fatty oil re- 5. A marine engine lubricant capable of formsults in poor emulsification unless the basic caling a stable emulsion when in contact with an cium salt is also present. Test 5 illustrates the aqueous medium, containing from 2% to 5% of value of the basic calcium salt specified in Exblown rapeseed oil and from 0.1% to 5% of basic ample I, in comparison with the corresponding calcium salt of oil-soluble petroleum sulfonic neutral salt. A comparison of tests 2 and 7 illusacid and the balance being a mineral oil.

trates the beneficial efiects of the basic calcium 3o 6. A marine engine lubricant capable of formsalt on mineral oil compositions containing blown ing a stable emulsion when in contact with an fish oil. aqueous medium, containing from 2% to 5% of The marine engine lubricants of this invention blown fish oil and from 0.1% to 5% of basic calpossess very satisfactory storage stability and cium salt of oil-soluble petroleum sulfonic acid .substantially no deposition occurs even after long and the balance being a mineral oil. storage at low temperatures, for example, 0 C. 7. A marine engine lubricant capable of form- Moreover, the compositions are fully compatible ing a stable emulsion when in contact with an with commercial grades of blended lubricants aqueous medium, containing from 2% to 5% of available for use in the lubrication of marine enblown semi-drying fatty oil and from 0.1% to 5% gine bearings. '40 of basic alkaline earth metal salt of oil-soluble Although this invention has been described petroleum sulfonic acid and the balance being a with the particular reference to the use of the mineral oil.

lubricating compositions as lubricants for marine 8. A marine engine lubricating composition engine bearings, the lubricating compositions of containing the following components in the folthis invention can be applied with advantage in lowing proportions:

other cases where lubrication in the presence of Parts by weight aqueous liquids or water vapor is necessary. Blown rapeseed oil 3 Thus, they can be used in the lubrication of Basic calcium salt of oil-soluble naphpumps and rock drills which have to operate in tha sulfonic acids 0.25

the presence of water or saline solutions. Acid refined mineral lubricating oil Balance In addition to being excellent marine engine lubricants, compositions of this invention may be marme engm? lubrlcatmg composition utilized as flushing oils, rust inhibiting oils, cutcmtammg components in the ting fluids and for various other industrial applilowing propormons:

cations. Parts by weight I claim as my invention: Blown fish oil 3 1. A marine engine lubricant capable of form- Basic calcium salt of oil-soluble naphing a stable emulsion when in contact with an tha, sulfonic acid 025 aqueous d um, containing from 2% 0 of Acid refined mineral lubricating oil Balance blown rapeseed oil, 0.1% to 5% of basic alkaline earth metal salt of an oil-soluble petroleum sulmanna engine lubricating Composition ionic acid and the balance being a mineral oil. ffial ing the following components in the ml- 2. A marine engine lubricant capable of formlowmg proportlons:

ing a stable emulsion when in contact with an Parts by weight aqueous medium, containing from 2% to 5% of l wn fish Oil 3 blown fish Oi1,0.1% to 5% of basic alkaline earth Basic calcium salt f Oil-soluble p metal salt of an oil-soluble petroleum sulfonic sulfmic acids 0.25

acid and the balance being a mineral oil. i free tallqw 1.5 3. A marine engine lubricant capable of form- Acld refined mmeral lubricating Oil Balance mg a Stable emulslon when m Contact Wlth an 11. A marine engine lubricant capable of formaqueous i m, containing from t0 0f ing a stable emulsion when in contact with an blown fish oil and from 0.1% to 5% of basic aqueous medium, containing from 2% to 5% of barium salt of oil-soluble petroleum sulfonic acid blown semi-drying fatty oil and from 0.1% to 5% and the balance being a mineral oil. of basic alkaline earth metal salt of oil-soluble 9 n 10 petroleum suii'onic acid and the balance being a Number Name Date mineral lubricating oil. 2,270,577 Bergstrom Jan. 20, 1942 WILFRED POHL. 2,470,537 Waugh May 17, 1949 2,493,483 Francis Jan. 3, 1950 REFERENCES CITED 5 The following references are or record in the OTHER REFERENCES file of this patent: "Lubrication of Industrial and Marine Ma- UNITED STATES PATENTS chinery, Forbes, John Wiley 8: Sons, Inc., N. Y;, Number Name Date 1 iti s r A t A ts Atl P d as ur ace 0 ive gen as ow er 1,998,767 MacLaren Apr. 23, 1935 c copyright 19481 pages 1 and 19 2,231,168 Lazar Feb. 11, 1941 

7. A MARINE ENGINE LUBRICANT CAPABLE OF FORMING A STABLE EMULSION WHEN IN CONTACT WITH AN AQUEOUS MEDIUM, CONTAINING FROM 2% TO 5% OF BLOWN SEMI-DRYING FATTY OIL AND FROM 0.1% TO 5% OF BASIC ALKALINE EARTH METAL SALT OF OIL-SOLUBLE PETROLEUM SULFONIC ACID AND THE BALANCE BEING A MINERAL OIL. 